Q179 / 180 · KCET 2016 · Physics
In a transistor, the collector current varies by \( 0.49 \mathrm{~mA} \) and emitter current varies by \( 0.50 \mathrm{~mA} \).
Current gain \( \beta \) measured is
Current gain \( \beta \) measured is
- Correct answerA19
- B\( 150 \)
- C\( 99 \)
- D\( 100 \)
Solution
Given, collector current variation, \( \Delta I_{\mathrm{c}}=0.49 \mathrm{~mA} \) emittercurrent variation, \( \Delta I_{\mathrm{E}}=0.50 \mathrm{~mA} \)
Now, current gain,
\[ \begin{array}{l} \beta=\frac{\Delta I_{C}}{\Delta I_{B}}=\frac{\Delta I_{C}}{\Delta I_{E}-\Delta I_{C}}=\frac{0.49 \mathrm{~mA}}{(0.50-0.49) \mathrm{mA}} \\ \beta=\frac{0.49 \mathrm{~mA}}{0.01 \mathrm{~mA}}=49 \end{array} \]
Therefore, current gain \( \beta \) is \( 49 \).
Now, current gain,
\[ \begin{array}{l} \beta=\frac{\Delta I_{C}}{\Delta I_{B}}=\frac{\Delta I_{C}}{\Delta I_{E}-\Delta I_{C}}=\frac{0.49 \mathrm{~mA}}{(0.50-0.49) \mathrm{mA}} \\ \beta=\frac{0.49 \mathrm{~mA}}{0.01 \mathrm{~mA}}=49 \end{array} \]
Therefore, current gain \( \beta \) is \( 49 \).
Hence, the correct answer is option: 'A'.